new to modding

Hi, so this is my first mod and am attempting to create a unique ability for my leader, Shrek. I thought what I wanted to achieve was fairly straight forward but I'm having some difficulty. Essentially, what I want is to give Marsh tiles a +3 Production and +2 Culture. This is to begin with, I'd...

I would like to add elements to the research part of the info panel. Nothing fancy, just some text. However, I can't find a tutorial anywhere and I have no idea what file it is in the Gamplay/XML folder.